Cal. Insurance Code § 1110

This article does not apply to combination automobile insurance policies in which one insurer issues a policy covering certain classes of insurance on a risk, and another insurer covers certain other classes of insurance on the same risk. This article applies to: (a) The issuance of a policy in which more than one insurer indemnifies the insured severally, jointly, or jointly and severally with other insurers for all or a specified portion of a risk. (b) The issuance of a policy which is subject to an automatic reinsurance agreement under which several insurers participate with the insurer or insurers issuing the policy to the same extent as though they were primary insurers, and the contract is negotiated upon the basis of such reinsurance and the policy makes reference to the fact of such reinsurance. (c) Policies issued pursuant to a plan providing for the allocation among various insurers of risks who have been unable to procure such insurance without resort to the plan.